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djgarrett21 wrote:
Phenolics are getting better but have limited use in structures due to their lower mechanical properties. My profession is aerospace with most of my experience using composite materials for structural applications - epoxy as well as BMI and polyimide resin systems. BMI's and polyimide's are the standard for high temp structues but they come at a cost - they can easily be an order of magnitude more expensive than epoxies and the curing process can be very difficult. They are basically out of reach for the bicycle and sporting goods industries right now.

...

They claim it is the resin but in my experience such a resin doesn't exist for sporting goods nor does a company the size of Alto have the expertise or resources to develop it.

AFAIK, it's only the brake track that is treated differently. I'm guessing that since it's just the track, it doesn't have to be as strong mechanically. Also, my impression is that the amount of resin used for the track is significantly less than that for the rest of the wheel. Which means that even though phenolics are more expensive, they may end up not contributing as much to the overall cost of the wheel. Finally, if such resins can already be acquired and used, Alto may not have had to expend significant resources on R&D.

It is likely that I have no idea what I'm talking about so please take with plenty of salt

Leviathan wrote:...and that, right there ladies and gentlemen, is why I still come back to this forum after all this time despite the number of posters, (especially on this thread it would seem) who are more keen to "hate you" and be right, than actually understand.
Helpful and insightful post, thanks

My problem is Calnago entered the thread with a thinly veiled “discs are just marketing” rant. That was neither insightful or helpful, and has no basis in fact. I’m tired of it. I will call you out on it. I think I’ve been pretty consistent in pointing out “just the facts” such as how the Alto rim lags (braking effectiveness) and where Boyd’s video was running at 15km/h.

antonioiglesius wrote:
AFAIK, it's only the brake track that is treated differently. I'm guessing that since it's just the track, it doesn't have to be as strong mechanically. Also, my impression is that the amount of resin used for the track is significantly less than that for the rest of the wheel. Which means that even though phenolics are more expensive, they may end up not contributing as much to the overall cost of the wheel. Finally, if such resins can already be acquired and used, Alto may not have had to expend significant resources on R&D.

It is likely that I have no idea what I'm talking about so please take with plenty of salt

I would have assumed they’d use the “additives” throughout the rim, but I guess it makes too much sense that they’d only be using it during the filament-winding processs. It just seems dubious that such a small surface area could result in that much more dissipation.

If anything, it’s probably better compaction / fewer imperfections allowing one rim to survive over another in a test like this.

You're spot on, Tobin. We do have to use the same resin throughout the rim because it aids in the fact that the sidewall and spoke bed act as a heat sink to better distribute and eventually dissipate heat from the brake track.

BobbySweeting wrote:You're spot on, Tobin. We do have to use the same resin throughout the rim because it aids in the fact that the sidewall and spoke bed act as a heat sink to better distribute and eventually dissipate heat from the brake track.

WHY ARE YOUR 52MM RIMS ACTUALLY 50MM?
Are you that far off in your mold calculations?

We do have to use the same resin throughout the rim because it aids in the fact that the sidewall and spoke bed act as a heat sink to better distribute and eventually dissipate heat from the brake track

Interest thread (including conspiracy theories regarding why everyone should ride disc) . Heat dissipation from a rim seems to be paradox requiring design trade offs. From the standpoint of maximizing heat dissipation you want turbulent flow (laminar flow is an insulator of sorts) but from a perspective of minimizing drag you want laminar flow. Maybe the wheel manufacturers that have a dimpled rim surface (greater area and more turbulent) are impacting more than braking power.

Flrider: I can't disclose a ton of details regarding the molding process, but we're using silicone and fiber tape as part of the molding technique and release, which helps to get the rim out in a clean fashion without creating high and low spots that need sanding. Those layers, plus flashing, are likely what you are noticing when you measure the rim. The naming of our rims is based on the actual cutting dimensions of the steel, which are based on the solid model of the mold. But there is more to making a rim than just the steel mold and the carbon.

I'm happy to send you the CC52 solid model (which I'll probably post up on our website soon), or you can visit our machine shop to see where the molds are made. Please let me know if you are interested in either option! We definitely do not want any disgruntled customers, or anyone with misinformation about our products.

Ok, so if your 52mm comes out 2mm smaller at 50mm (if we all buy your BS)

Then how does your 28mm come out 2mm larger at 30mm.

And how does every single other wheel in the world have the same depth as their molds.
Molds are done by a bladder or some pressure pushing outward against a steel mold to form the shape, right? So if the mold is a certain size then how can one size be smaller by 2mm and another size larger by 2mm?

Flrider: Are we talking about our rim brake or disc brake models? The layup is different on our CCX line because there is no brake track to filament wind. It's just a different process and different mold release technique. Since you mentioned the 28, you must be referring to the CCX28 and CCX52. They should measure close to 28 and 52 or slightly under. Our CCX28 certainly don't not measure out to 30 unless there is flashing on the seam that was not removed sufficiently, which is possible.

Again, if you are in Florida, I will literally show you where the molds are cut. I am on this forum on a Sunday night because I care about our brand, our product, and our customers. After spending a LOT of money on this resin development, I certainly don't want our customers believing that we are doing anything that isn't from the ground up! The world does not need more wheel brands, but we are doing things that are helping to drive the industry forward.

TobinHatesYou wrote:You have 7 total posts, all specifically targeting Alto’s rim profiles. How about you take Alto/Bobby up on his offer instead of parroting the same thing over and over?

It's because they are obviously lying to their customers about their own molds. Instead of just saying that they found a rim they are happy with and are happy to offer, they chose to lie. If they would have just told me that they are using an open model rim that passes all their testing I would have understood and been ok with buying wheels.
Instead they chose to lie to me to make themselves look better. They are getting caught up in it and are making up more lies.

Make a 52mm mold in Florida and then somehow it magically turns into a 50mm rim that just so happens to have the exact same profile as other rims on the market.

How are we supposed to trust anything they say when this blatently obvious lie is being told.

They are basically saying they believe all their potential customers are idiots and can't figure this out.

Here is the side by side of the Pacenti 50mm with the Alto "52mm" again for reference.

Flrider: I'm not sure what else I can do or provide in order to help you. I'm also not sure why you believe that the CCX52 rim measures out to 50mm. It is likely slightly under 52mm for the reasons that I mentioned, but I very much doubt that it is 2mm off. I'm happy to measure a rim tomorrow with the micrometer and post a photo, if you'd like. In fact, that may be the best thing to do. Would you like me to take some measurement photos tomorrow and post them here or email them to you?

We just created a carbon clincher that is the first in 20 years that cannot delaminate under heat stress, and we are now being accused on a forum of buying open mold rims. I am doing my best to show you otherwise, but I think I'm out of ideas! Haha. Please come to Sarasota and we can give you a tour of the machine shop.

BobbySweeting wrote:
Think about the use and required production protocol for disc brake wheels: no brake track (obviously) and no risk of brake rub at the rim. This means a few things. A manufacturer can use a very inexpensive resin, a lower modulus fiber, cheaper molding techniques (such as aluminum molds instead of steel), and can machine build the wheel instead of hand building them. This can all be done because it matters less if the wheel falls out of true, it matters less if there are interior wrinkles inside the rim, and it matters less if the wheel is softer overall. As long as it doesn't crack, it's all good. If your rim brake wheel isn't dialed, you'll notice straight away! But if your disc brake wheel has a hop in it because the spoke tensions aren't even to begin with, most people probably won't notice or care.

How are any of these things a drawback for the consumer (as you seem to imply)? Maybe I'm misinterpreting your intent but just about everything you state seems to be in favor of disc wheels.
- "No brake track" = better aero properties, less weight, and one less design constraint
- "Inexpensive resin" = lower cure temp, less cost to the consumer and better toughness properties (toughness is a very good thing for bike wheels)
- "Lower modulus fiber" = Not true. There would be no reason for a wheel manufacturer to use a lower modulus fiber just because they are using a different resin - why add the weight? Strength properties are dominated by the fiber not the resin. As an aside, lower modulus fibers are less brittle and can be more desirable in many applications. Again, toughness is a good thing for bike wheels.
-"Cheaper molding techniques" = Again, less cost to the consumer. This is a win.
- "It matters less if the wheel is softer overall" = There is no reason a disc wheel would be "softer" in any way that would matter to the rider.

Generally you make the case that disc wheels are more tolerant and less costly than rim brake wheels.

BobbySweeting wrote:
DJGarrett21: If you check out our test video, you will see that we are controlling the energy into each rim at 1200 Watts. The conductive properties of our resin is absolutely the most technologically advanced in the cycling industry. As far as our expertise goes, I do think that a small brand with multiple engineers and material scientists has the ability to develop something of this nature. I can appreciate your opinion because it was a significant undertaking and not something that came about over night. It was about 8 months of R&D. Unfortunately the resin additives and the exact thermoset properties are a trade secret at the moment, and not something we're willing to disclose. Our intent was to show a very transparent test regarding its performance, so hopefully that will be enough to convince you!

Again, I could be completely wrong but it is very difficult to take your claims at face value. Given: rampant (dubious) claims in the cycling industry of exclusive fiber and matrix properties, your wheels somehow being such an extreme outlier in your test results, lack of any data to back your claims of a new resin, the prohibitive cost of developing a new resin system - a reasonable and knowledgeable person would have to conclude that we aren't getting the full story.

You can disclose plenty of information about the development, testing, composition, and properties of your resin without giving up any information that would compromise your intellectual property/trade secrets.

Until you share relevant data or another party independently verifies your test results I'd suggest consumers be very skeptical of your claims.

Oh yeah I almost forgot. I see no evidence your wheels are filament wound which is a whole other can of worms. Looking at time 17:50 of your video, those are uni plies not filament wound toes.

Leviathan wrote:...and that, right there ladies and gentlemen, is why I still come back to this forum after all this time despite the number of posters, (especially on this thread it would seem) who are more keen to "hate you" and be right, than actually understand.

My problem is Calnago entered the thread with a thinly veiled “discs are just marketing” rant. That was neither insightful or helpful, and has no basis in fact. I’m tired of it. I will call you out on it. I think I’ve been pretty consistent in pointing out “just the facts” such as how the Alto rim lags (braking effectiveness) and where Boyd’s video was running at 15km/h.

It is not at all a "thinly veiled 'discs are just marketing rant'". It was intended to provoke some thought, which it did and I really appreciate the responses from the likes of @Leviathan, @DJGarrett21 and others who clearly have more knowledge on resin technology and their applications than I do. And you too, @BobbySweeting for hanging in here on this thread.

I've always maintained that discs have their place, just that that place may not be on the highest end road bikes. And this is a huge dilemma for the big companies who promote their wares in events like the Grand Tours. It does not follow that road bikes should automatically adopt mountain bike technology for many reasons. A few being that road bikes are never axle deep in mud, road tires are much skinnier this not requiring scads of clearance that discs can provide, and then there's this stuff called pavement between these skinny tires and the dirt, leaving a relatively small contact patch where the rubber meets the road so to speak. So Tobin, please get it through your head that if I had a mountain bike or even a commuter (and rode every day to work regardless of weather), then sure, give me the discs. But for a nice road bike... no thanks. If I'm going to have to carry around ~500grams of extra weight on my bike all else being equal, I would rather it be used to make the frame stonger than on brakes. So I'm happy for you that you like your disc brakes, but don't hate others because they prefer their rim brakes. There are good arguments for both to exist in various scenarios.

And it appears that @BobbySweeting (a principal at Altos) personally prefers rim brakes too, and he states a few of the same reasons why I prefer them as well. Basically, they are simple, and they work. But as the large companies and frame manufacturers are "pushing" disc brakes, so too smaller companies must follow. I may not be a resin expert, but I do know how business works. And as several have pointed out, the cost of producing a carbon rim brake clincher that is completely void of any heat or safety issues may simply be too much for the bike industry to swallow. Especially when they can just port over their existing mountain bike braking systems along with all their added complexities and weight with little in the way of expensive new R&D. Again, this is "bottom line" decision making, there's no mistaking that. To think otherwise would be very naïve.

@BobbySweeting: I'm liking your tenacity in pursuing a holy grail of carbon clincher or even just a reliable technology for any rim brake carbon wheel, clincher or tubular. I do believe it can be done, but yes, probably at a very high cost. You must somewhat believe in the future of rim brakes, otherwise there would be absolutely no point in Altos pursuing this path. But I can see this market going forward being relatively small potatoes for the big guys, and as you also point out, there is likely a huge cost savings in production if they don't have to build wheels to as high a standard as carbon clinchers would require. Although I'd hate to think that disc wheels could potentially mean that rim quality going forward would suffer as a result, which if they adopted some of the cost cutting production measures and methods you mention would surely be the case. Rather, I see the cost savings in being able to consolidate the braking technology between road and mountain into one. Which is really what they are doing. I don't for a second believe that Campagnolo was ever truly committed to disc brake technology on road bikes, hence their dragging their feet on coming up with an offering. But compared to the likes of Shimano, they are tiny. And so too.... they must follow the trends that the big boys lay down for them. Business is business. Sometimes we innovate, sometimes we follow... but at the end of the day, we need to make money.

I guess we'll have to wait and see how it all plays out. I don't pretend to think that the large manufacturers are going to let the pros continue to ride rim brakes forever, and that will be too bad, because the pro ranks and the Grand Tours are really where the most rim brake benefits can be had... by virtue of their simplicity, wheel changes, mechanics time, and probably most important of all.... less weight. And if I had to choose between two bikes...both at 6.8kg, but one had 500g less frame material than the other which had disc brakes, I'd for sure be choosing the one with the beefier frame.

And before someone yells foul for turning a thread about new carbon wheel technology into a disc vs rim brake discussion, I'll say the two are really inextricably tied together. Personally I still believe that if one can solve the heat and reliability issues of a carbon (or other suitably light strong material) rim surface for braking at a cost acceptable to the consumer, then you'd now have the biggest disc you can think of to work on. And with hydraulic rim calipers added to the mix, then there would be zero advantages to disc brakes on a high end road bike, aside from running really really big tires. But where's the profit in that, especially when people are so ready to just bend over and accept the technology that is already developed for our mountain bikes.

We used to have these things called threaded bottom brackets. They worked. They were simple. I miss them. I'd hate to see rim brake technology go that way too. It has a place, right at the top of pro level road racing. The unfortunate truth is that that place exists to promote what the manufacturers deem will reap the most profit, and that right now, is disc brakes for everyone. And that, is just business, for better or worse. Same as it ever was.

DjGarrett21: Regarding the rim brake vs disc brake thing, I certainly don't need to get into that with you. It's a long conversation that many many people have had, haha. I just wanted to give you my 2 cents and my personal opinion. I like disc brakes! I simply prefer rim brakes, and feel as though the disc brake system may have been pushed into the industry for reasons that aren't entirely performance related.

Regarding our testing: The independent party you seek would be Spark Wheel Works. They are a retailer and custom builder in California that sells every brand in the test. Please call Ryan Mason at Spark and he can confirm the unbiased and blind nature of this test. We were as shocked as everyone by the results, and honestly a bit disappointed. We wanted it to be close, or maybe even for someone to do better than the new Alto rim. I knew that would make it more believable for people at face value. When our rim went 40min and the next rim went 5.5min, I obviously knew people would be skeptical. Hell, so would I. But think about it this way: how would we be able to design a test so that we would smash everyone, if we didn't know ANYTHING about the other brands or how they would perform? We had one rim from each brand, and there is zero information online about how they would perform in a test like this. That's why we wanted to do it! But if you need verification, please call Ryan.

Our rims absolutely are filament wound, you will not find a parting line anywhere on the sidewall. I'm surprised that you work in the composites industry but cannot tell this from seeing an image of our rims, because it's fairly obvious. If you'd like, I can ask Topkey for a video of the fibers going into the resin bath and into the feed and can send it your way!